Improvement in securing knobs to their shanks



ttl tant @that THOMAS-J. SLOAN, OF NEW YORK, N. Y.

Lette/rs PatentNo. 88,919, dated April 13, 1869.

IMPROVEMENT IN SECURIN G- KNOBS TO THEIR SHANKS.

'l'ha Schedule referred to in these Letters Patent and mal-:lng part of the sama.

To all whom it may concern:

Be it known that LTHOMAS J. SLOAN, of the city, county, and State of New York, have invented a new and useful Improvement in Securing Metallic Shanks to Knobs made of porcelain and other earthenware; and 1 do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making part of this specification, iu which- Figure 1 is an elevation of a knob with the shank secured according to my said invention;

Figiu'e 2, a section of the knob and shank, taken in the plane of the axis of the shank;

Figure 3, a section taken in the plane of the line A a of fig. 2; and

Figure 4, a section ofthe knob before the shank is inserted.

M y saidinvention relates to an improvement on the well-known method of securing metal Shanks in knobs made of porcelain and other earthenware, by running molten metal into the cavity of the knob, and around that portion of the metallic shank inserted in the said cavity.

The metal, which is poured into the cavity in the molten state, must be such as will melt at a low temperature, and hence, comparatively soft when cold. Such metals are ductile, and readily yield to pressure, and for that reason the knobs soon become loose on their metallic shanks.

The object of my invention is to avoid this defect; and to this end My said invention consists in making that part of the metallic shank which is to be inserted in the cavity of the knob with projecting spurs near the end, and making the cavity in the knob of such a form that the metal shank can be inserted into it freely and then turned a short'distance, so that the spurs will becarried under shoulders formed by recesses in the sides of the cavity, and as far as the form of such recesses will permit; aud in using, in connection therewith, what I denominate anchor-pieces, of hard metal, one

for each spur on the shank, and by any suitable instrument holding' the said anchor-pieces between the spurs and the collar, 1or ilanch ou the shank, while iuserting the `shank in the cavity of the knob, and letting them go, so that when thespurs are carried into the lateral recesses bythe turning of the shank, the said `hard-metalV anchors shall drop iubchiud the spurs to anchor them, and then pouring molten I'n'etal or cemeut into the cavity, to rmiy bind all the parts together.

I n the accompanying drawingsa represents a knob, made of porcelain or other earthenware, and l b, the tubular metal shank, formed with a collar, or anch, to rest against the inner face of the knob, and with the part c, which is to be secured in the cavity of the knob, formed with two spurs, d d, projecting from opposite sides, and near theextreme end thereof. In the direction of the length of the shank, the spurs Z d, I prefer to make of less than half the length of the part c of the shank, leaving an open-space between the spurs and thecollar, or anch, of a little more than the length of the spurs.

lhe cavity in the knob is cylindrical, with grooves c e ou opposite sides, corresponding with the spurs d d and extending the whole depth of the cavity, and from each of these grooves there is a lateral recess, or groove, the upper face of which is inclined, so that when the shank is inserted and turned, the two spurs will be carried into the recesses, or lateral grooves, the upper inclined faces of which will draw the shank i'n, until the collar, or anch, is brought into close contact with the inner face of the knob.

When inserting the shank into the cavity ofthe knob, two metal blocks, or anchor-pieces f f, of a slightly wedge form, are held by any suitable means in the spaces between the -spurs al d and the shoulder, or collar, until they enter the grooves c e of the knob, and then liberated; and when the shank is fully inserted in the cav ity, and turned as before stated, they drop behind the spurs el d into the grooves e c, and there firmly anchor the spurs, so that the shank cannot ,be turned back. Molten metal, by preference, is then run into the cavity, to iill all the vacant space, and hold all the parts in place.

By the means above described, it will be seen that the shank is held in place in the cavity by the contact of hard metal and the substance of the knob, the soft metal merely securing the anchor-pieces in place, thereby avoiding the defect heretofore experienced.

What I claim as my invention, anddesire to secure by Letters Patent, is

In combination with the knob, having a cavity substantially such as described, the metal shank, with projecting spurs, and the anchor-pieces, held in place by soft metal, run in in the molten state, substantially as and for the purpose specified.

THOS. J. SLOAN.`

-Witnesses:

WM. H. Brsnor, ANDREW DE LAonY. 

